Abstract
The present investigation deals with the numerical analysis of steady-state laminar buoyancy-driven convection in an inclined triangular enclosure filled with fluid saturated porous media using the Darcy law equation. One wall of the enclosure is isothermally heated and the other is cooled, while the remaining wall is adiabatic. The effect of inclination angle on natural convection is investigated by varying the angle of inclination (φ) between 0° and 360°. The governing transformed equations are solved numerically using a finite-difference method. Obtained results are shown in the form of streamlines, isotherms, mean Nusselt numbers and dimensionless stream function for different values of the Rayleigh number Ra in the range 100 ≤ Ra ≤ 1,000. It is found that the values of the maximum and minimum mean Nusselt number are reached for φ = 330° and φ = 210° , respectively. However, the lowest flow strength is formed at φ = 240° for all values of Ra.
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Abbreviations
- g :
-
gravitational acceleration
- Gr :
-
Grashof number
- H :
-
height of triangle
- K :
-
permeability
- L :
-
length of bottom wall of triangle
- n :
-
denotes the direction normal to the inclined wall of the triangular cavity
- Nu y :
-
local Nusselt number
- Nu m :
-
mean Nusselt number
- Ra :
-
Rayleigh number for a porous medium
- T :
-
fluid temperature
- u, v :
-
velocity components along x and y axes
- x, y :
-
dimensional coordinates along the horizontal and vertical walls of the triangular enclosure, respectively
- X, Y :
-
dimensionless coordinates
- α m :
-
effective thermal diffusivity of the porous medium
- β :
-
thermal expansion coefficient
- φ :
-
inclination angle
- θ :
-
dimensionless temperature
- υ:
-
kinematic viscosity
- ψ :
-
dimensional stream function
- Ψ:
-
dimensionless stream function
- C:
-
cold
- H:
-
hot
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Varol, Y., Oztop, H.F. & Pop, I. Influence of inclination angle on buoyancy-driven convection in triangular enclosure filled with a fluid-saturated porous medium. Heat Mass Transfer 44, 617–624 (2008). https://doi.org/10.1007/s00231-007-0290-3
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DOI: https://doi.org/10.1007/s00231-007-0290-3